Crate anagram

Functions

count	Count the number of anagrams that can be formed from a word
get_next	Get the next lexicographically greater anagram (or find the next lexicographically greater permutation of the given string) This function will return either the next greater permutation or the given word if it is already the greatest permutation Examples: “abc” -> “acb” “cba” -> “cba”
is_anagram	Check if a word is an anagram of another word
occurences	Count the number of occurences of an anagram in a word